In the latest cutting-edge version, glyphs that have been previously saved with a colour highlight and were also highlighted (i.e. selected) are black:
Known issue. It is probably fixed in the next cutting edge.
I just uploaded a new version.
macOS Sierra, G2.5.2 
Unfortunately this is still there in 1183. I did not have the problem in 1181.
Have you tried 1184?
Yes. It is fixed in 1184. Thanks.
Great. Though it’s telling me 1183 is the latest version, and not giving me the option to download an update?
You can download it manually, here:
That works - many thanks